Modeling and Simulation of Gas, Oil and Water Flow in a Catenary-Shaped Riser

Abstract

In this paper, a one-dimensional multiphase flow model in a catenary-shaped riser is presented, as well as results obtained through dynamic simulations. The model considers continuity equation for gas, oil and water phases and a simplified momentum equation without inertia terms (nopressure-wave or NPW approximation) for the phases flowing together. Oil and water phases are considered to have the same velocity and are homogenized. Slip between the liquid and gas phases are taken into account by using a drift flux model. Mass transfer between the oil and gas phases are calculated using the black oil model. The numerical solution of the equations is obtained using the method of characteristics. As result of the simulations, the evolution of the pressure at the bottom of the riser is shown for different inflow boundary conditions.